Huñis graduated in 1973 from the University of La Plata School of Medicine, Argentina. His postgraduate training in Internal Medicine was completed at Ramos Mejia Hospital in Buenos Aires, Argentina. Fellowships in Medical Oncology were completed at the Universidad del Salvador and Chair of Oncology based at the Central Military Hospital, Buenos Aires, Argentina. He completed his oncology fellowship at the Miami Cancer Institute, Florida, USA. Huñis became board certified oncologists with the academic. Scientific and institutional endorsement of the Argentina association medical oncology cancer society. In 2004 obtained the re certification of the National Academy of Medicine.

Since 1996, Huñis has been an Associate Investigator in the ATLAS study, Oxford University and principal clinical investigator in multicenter studies of Phase II and Phase III breast cancer, lung, melanoma, and cancer-related pain